Deep Mining at Sunagawa Colliery

Sunagawa Colliery has managed to solve many difficult problems since 1914 and the technical innovation took place in 1964 when the colliery employed hydraulic mining. Subsequently, the hydraulic mining has been steadily improved widening the range of its application. The colliery is now working steeply inclined seams at the depth of 900 to 1000 meters below surface. The author intends to introduce parts of the results successfully practiced in the deep mining at Sunagawa Colliery.